Fill Dirt Calculator

Filling a low spot, raising a grade, or backfilling? Enter your area and fill depth to get the loose volume and tons to order, with a compaction allowance so the finished grade ends up where you want it.

Fill Dirt Details

Length

Width

Fill Depth

Compaction Factor

Fill Dirt Density

tons/yd³

Enter your area and fill depth to see how much dirt you need.

The formula

Loose yd³ = (L ft × W ft × Depth ft) ÷ 27 × (1 + Compaction %) → Tons = Loose yd³ × Density

Note the depth here is in feet — fill projects usually move more material than a thin aggregate layer. Fill dirt runs lighter than rock, around 1.2 tons/yd³ loose, though moisture swings this substantially.

Settling and compaction

Fill placed without compaction will settle on its own over months — fine for a rough berm, unacceptable under anything structural. For lawns and general grading, 10–15% extra covers natural settling; under slabs or pavement, fill must be placed in compacted lifts to engineered spec.

Frequently Asked Questions

How many tons is a cubic yard of fill dirt?

Around 1.0–1.3 tons loose depending on soil type and moisture; the calculator defaults to 1.2 tons/yd³.

Can I build on fill dirt?

Only if it’s placed and compacted in lifts to engineering spec. Uncontrolled fill settles unevenly and is the classic cause of cracked slabs.

What’s the difference between fill dirt and topsoil?

Fill dirt is subsoil — low in organics, stable for raising grade. Topsoil is the organic-rich layer for growing; it decomposes and settles, so it belongs on top, not underneath.